How to extract read and set values from a scalar attribute¶

Intended audience: developers, Programming language: c++

The following example will show how you can extract the read and set values from a scalar attribute. In the example, the attribute is a Tango::DevDouble.

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Tango::DevVarDoubleArray * attr_val;
Tango::DevDouble read_value, set_value;
try {
    Tango::DeviceAttribute dev_attr =  tg_device_proxy->read_attribute("attr_name");
    dev_attr >> attr_val;
    read_value = (*attr_val)[0];
    set_value = (*attr_val)[1];
    delete attr_val;
}
catch(Tango::DevFailed &e){
    Tango::Except::print_exception(e);
    throw;
}

Note

The operator ** >>** will allocate the memory for the Tango::DevVarDoubleArray but the programmer should free this memory when the work is done with this variable.